Ethereum Account Abstraction (ERC-4337), Part 2: Implementation

If you’re building on Ethereum, ERC-4337 lets you move beyond standard EOAs. In Part 2 of my series, I walk through implementing a smart account and connecting it to a frontend.

What You Build

• A smart account that validates owner signatures
• Executes arbitrary contract calls
• Handles gas via UserOperations
• Connects seamlessly to a frontend and bundler

How It Works

1. Encode your target contract call and wrap it in the account’s execute() function.
2. Estimate gas using a bundler with a special estimation signature.
3. Sign the UserOperation and submit it to the bundler.
4. EntryPoint validates and executes the operation, reimbursing the bundler from the account’s deposit.

Why It Matters

• Full on-chain validation without trusting the bundler
• Deterministic execution for arbitrary calls
• Minimal, complete ERC-4337 workflow

For the full walkthrough with code snippets, check out my Medium article: Part 2: Implementation